Dental plugger.



N0. 639,536. Patented Dec. I9, |899.

C. H. DAVIS. Y 'DENTAL PLUGGER.

(Application led July 29, 1899.)

( N 0 M o d el.)

UNITED STATES PATENT CEETCE.

CHARLES II. DAVIS, OF WORCESTER, MASSACHUSETTS.

DENTAL PLUGGER.

- lSFEGIFICATION forming part of Letters Patent No. 639,536, dated December 19, 1899 Application filed J'uly 29, 1899.

To all whom. t may concern;

Be it known that I, CHARLES H. DAVIS, a citizen of the United States, residing at i/Vorcester, in the county of Worcester and Commonwealth of Massachusetts, have` invented a new and usefulImprovementin Dental Pluggers, of which the followingis a specification, accompanied by drawings forming a part of the same, and in which- Figure l represents a side elevation of a den; tal plugger embodying my invention. Fig. 2 is a central longitudinal sectional view. Fig. 3 representsl a detached view of a toolholder shown partly -in sectional view and containing a plugging-tool adapted to impart a blow by a direct forward movement, a portion of the tool-holder being shown in sectional view in order to disclose the mortise therein and the beveled-faced actuatingspindle. Fig. 4 is a side elevation of the tool and tool-holder shown in Fig. 3. Fig. 5 is a view of the sliding ring and elastic blade by `which the screw-threaded collar on which the rotating head is mounted is held from turning. Fig. 6 represents the tool-holder carrying a plugging-tool adapted to imparta blow on its reverse or backward motion, and Fig. 7 represents a screw-threaded collar upon which the rotating head is mounted.

Similar letters refer to similar parts in the different views.

- The object of my present invention is to provide a mechanism for actuating a plug-- ging-tool in that class of dental pluggers in which the plugging-tool is arranged to be operated at an angle to the direction of the movement of the reciprocating blow-imparting plunger, whereby the same actuating mechanism will serve to impart ablow to the plugging-tool upon its forward stroke when plugging-tools of the kind shown in Fig. 3 are employed and also to impart a blow to the plugging-tool upon its reverse stroke when curved or bent plugging-tools are employed like that shown in Fig. 6, without requiring any change in the actuating mechanism,

thereby enabling blows to be imparted to the plu gging-tool upon either its forward or backward stroke as either a straight or curved plugging-tool is used. I accomplish these objects by means of the mechanism shown in Serial No. 725,547. (No model.)

the accompanying drawings and hereinafter described; and my invention consists in the novel construction and arrangement of the claims.

In the accompanying drawings I have represented an actuating mechanism embodying my invention mounted :in a dental handpiece like that described in Letters Patent of the United States No. 522,291, issued to me July 3, 1894,which comprises ahandpiece provided with a collar capable of rotating thereon in a plane at an oblique angle to the axis of the handpiece and having mounted thereon an elbow-shaped head carrying a tool-holder, whereby the aXis of the tool-holder may be placed at varying angles to the axis of the handpiece.

Referring to the accompanying drawings, A denotes the outer casing of the handpiece, provided with a tubular sleeve A', having a groove at its end in which is held a rotating collar A2, capable of turning in the groove with its axis at an oblique angle to the axis of the handpiece and having an external screw-thread upon which is screwed a rotating elbow-shaped head B, carrying a tool-holder B' with its axis arranged at right angles to the axis of rotation of the head B and capable of a slight longitudinal reciprocating motion.

The tool-holder B is provided with an elongated mortise B2, adapted to receive the tip C3 of 'an actuating-spindle C, held concentrically in the closed endof the sleeve A and capable of a sliding motion. The opposite end of the spindle C is provided with a blunt point C2, bearing against the beveled end D of a reciprocating plunger D, which is attached at its opposite end by a pin D2 to a tube E, capable of sliding in the casing A. The sliding tube E and plunger D are forced toward the spindle C by means of a spiral spring F, having one of its endsv bearing against a plug E', screwed into the end of the sliding tube E and having itsv opposite end bearing against the adjustable collar F', held upon the screw-threaded hub G of a plug G, by which the end of the casing A is closed. An opening F2 in the casing A is provided to allow the collar F to be adjusted on the hub G' in order to vary the force of the spring F.

operating parts as pointed out in the annexed- IOC) The sliding tube E is drawn back against the tension of the spiral spring F by means of a rotating cam Il, acting-againsta cam-surface H' upon the plug E. The cam H is carried upon a shaft H2, having a spline connection with a cam H2, which is engaged by a cam H, attached to a rotating shaft H5 in alinement with the shaft H2 and journaled in the plug G and operatively connected by a coupling H6 with a exible driving-shaft in the usual manner.

The cams H3 and H4 are inclosed in a shell l, which contains a spiral spring I', by which the cam H3 is held normally in engagement with the driving-cam H4, causing the rotation ofthe shaft H5 in one direction to be communicated to the shaft H2, while the rotation of the shaft F5 in the opposite direction will cause the cam H3 to slide on the shaft H2 and against the tension of the spiral spring l', thereby disconnecting the shafts H5 and H2 whenever the motion of the driving-shaft H5 is reversed.

Vhen the shaft H2 is rotated, its attached cam H, acting against the canrsurface H' causes the sliding tube E and plunger D to be drawn back, thereby compressing the spiral spring F until the shaft H5 has` made one revolution, when the cam H suddenly releases the sleeve A and plunger D, allowing the spiral spring F to force the plunger forward and impart a blow to the pointed end C2 of the actuating-spindle C, thereby forcing the liattened tip C into the mortise B2 of the tool-holder. The flattened tip C of the spindle C is formed by slabbing the opposite sides of the spindle C, so as to form a lat blade at the end of the spindle, and the Width of the blade is reduced at its end to form a tongueC3 and form beveled edges C4 and C5 on` opposite edges of t-he blade.

The tongue (J3 is arranged to enter the mortise B2 and hold the tool-holder from turning, while the beveled edges Cl and C5 are adapted to strike against the end walls and B4 of the mortise B2.

In case the tool-holder is pushed into the head, aswhen the straight tool is employed, with its end a bearing against the work, then the beveled edge C4, as the spindle C is pushed forwardby the action of the plunger D, strikes against the end wall B3 of the mortise and imparts a blow tothe plugging-tool in the directionof the arrow l, Fig. 3; but in case a bent plugging-tool is employed then the pressure of the tip b of the tool against the work serves to draw the tool-holder out and bring the end wall B? in position to be struck by the beveled edge C5 ofthe actuating-spindle, causing a, blow to be imparted to the plugging-toolin thedirection of the arrow 2, Fig. G. The blow of theplunger D is therefore imparted tothe tool-holder in either direction, according to the plugging-tool which is used and the direction of the pressure of the tip of the plugging-tool upon the work, the force of the blow being always in a direction opposite to that of the pressure which is exerted upon the tip of the plugging-tool as it is held against the work by the operator.

As the plugging-tool is moved out or in by its pressure on the work the contact of the end walls of the mortise B2 will act against the beveled edges of the spindle C to reverse the movement of the spindle. For example, as the tool is pushed in by a pressure on the tip a the end Wall B3 will act on the beveled edge C4, and as the tool is drawn out by a pressure applied to the tip b the end wall B4 will act against the beveled edge C2, and in either case cause the spindle to be held against the end of the plunger.

In case a plugging-tool of the kind shown in Fig. 3 is employed with its tip held against the work the pressure of the tool upon the work will always be exerted to push the holder into the rotating head, while the force of the blow exerted by the plunger D would be exerted in the opposite direction to force the blow against the Work; but if a plugging-tool of the kind shown in Fig. G be used the pressure of the ti p of the plu ggin g-tool against the work will always tend to drawthe tool-holder out of the rotating head and cause the blow exerted by the plunger to be exerted in the opposite direction.

The actuating-spindle is held concentricall y with the rotation of the head B1 around the end of the sleeve A, so that the rotation of the head is always around the axis of the spindle C, in whatever position the rotating head may be placed, and the pointed end C2 of the spindle C will always be presented to the c'enter of the beveled end of the plunger D.`

I do not con tine myself tothe speciiic actuating mechanism for imparting a blow to the plunger D, as other well-known` mechanisms now used for this purpose in dental pluggers may be employed.

My present invention relates particularlyto that part of the mechanism which isemployed in communicating a blow of the plu'ngerD to the tool-holder carrying a plugging-tool, whereby without any change or adjustment of the actuating mechanism a blow may be imparted by the plunger tothetool-holder to either force it into or out of the head B, so that plugging-tools-of the character represented in Figs. 3 and G may be employed indiscriminately without change in the actuating mechanism.

The rotating collar A2 is cut apart. on` one side and is sprung into a groove formedinthe end of the sleeve A', the construction being substantially like that shown in UnitedStates Patent No. 522,291, above referred to. The

screw-threaded collar is provided onone of its edges with a notch A2, Vby which the collar may be dogged and held` from rotatingwhile the head Bis being screwed on or oit.

I provide the sleeve A with a longitudinal groove J deep enough to disclose theedge of IOO IIO

the rotating ring A2, and within the groove J, I place a blade-spring J ,havingits end curved at J2 and bearing against the bottom of the groove J. The opposite edgeof'the bladespring J is attached to a sliding collar J2. The bent end J 3 of the blade-springis adapted to engage the notch A3 by sliding the ring J2 toward the head B and hold the collar from rotating.

When it is desired to release the collar A2, the sliding collar J2 is drawn back against the end of the outer casing A and is held in place by the pressure of the bent end of the blade-spring J' against the bottom of the groove.

What I claim as my invention, and desire to secure by Letters Patent, is

l. The combination of a tool-holder provided With a recess presenting opposin g Walls to the action of an actuating-spindle, a reciprocating plunger and an intermediate actuating-spindle provided with oppositely-beveled edges arranged to receive the blow of said plunger and engage the recessed toolhold er,whereby the blow of said plunger is imparted to said tool-holder in either of two opposite directions, substantially as described.

2. The colnbination of a tool-holder provided with a recess or mortise, an actuatingspindle provided with a tongue on one end entering said recess or mortise, and having oppositely-beveled edges arranged to contact with the walls of said recess or mortise, and means for impartinga blow against the opposite end of said actuating-spindle, substantially as described.

3. The combination with a dental handpiece of a rotating head journaled on said handpiece, a reciprocating tool-holder held in said head, with its axis at right angles to the axis of rotation of said head, a reciprocating plunger contained in said handpiece, means for imparting a blow to said plunger, an intermediate actuating-spindle between said plunger and said tool-holder with its axis coincident with the axis of rotation of said head, said intermediate spindle being arentering said recess, and having oppositelybeveled surfaces arranged to engage the walls of said recess, or mortise, whereby a longitudinal movement of said spindle will impart i a longitudinal movement to said tool-holder, a reciprocating plunger arranged to impart a blow to said spindle, a spring arranged to force said plunger against said spindle and means for compressing and releasing said spring, substantially as described.

5. The combination of plunger D, means for actuating said plunger, tool-holder B having a mortise B2, spindle C having one end in contact With the end of said plunger, tongue C3 entering said mortise, beveled edges C4 and C5 arranged tov engage the Walls of said mortise and convey the blow of said plunger to said tool-holder in either direction, substantially as described.

6. In a dental plugger, the combination of a tool-holder, a spindle at right angles to said tool-holder and having a beveled surface at one end of said spindle to engage said toolholder and impart a longitudinal motion to said tool-holder, a reciprocating plunger by which a blow is given to the opposite end of said spindle and means for actuating said plunger, substantially as described.

7. The combination with a handpiece provided with a groove J of screw-threaded rotating collar provided with a notch A3, a head carried upon said collar, a blade-spring sliding in said groove and having its end adapted to engage the notch in said collar and means for sliding said blade-sprin g, substantially as described.

Dated this 26th day of July, 1899.

CHARLES H. DAVIS.

Witnesses:

RUFUs B. FowLER, ELIZABETH GRAY. 

